Clutch type speed responsive device with magnetic link



1954 e. A. WINTERBURN ETAL 2,668,043

CLUTCH TYPE SPEED RESPONSIVE DEVICE WITH MAGNETIC LINK Filed March 31,1951 f 17/ may G769 Ami-$655M)? Patented Feb. 2, 1 954 ED STAT PAT'E NTOFFICE CLUTCH TYPE SPEED RESPONSIVE' DEVICE. WITH MAGNETIC, LINKApplicationMal-cli 31, 1951, Serial-No. 218,631

22, Glaimsv. 1. This invention relates to a device for trans-- mittingmotion through combined hydraulic and magnetic: links, particularlyasappliedtoswitches for indicating or making effective the motionor restcondition of a driving mechanism; for thepurpose of controlling it orassociated devices.

It frequently desirable to supervise or control themode of" operation ofmachines having rotary or other motions. Examples of such supervision orcontrol are remote indication of the response' of an electric motor tothe operators. control; protective supervision ofamotor to insure thatit has slowed down or stopped before reverse power is applied, controlofone machine according to the operation of another machine;introduction of a time delay betweenthe start of oneoperation andthestart oi an-- other, and analysi'sof various machine-functions,(Dbjectsof the present invention areto-providearr improved. actuatingdevice which responds to rotary motion in either direction,which-distinguishes between. directions of motion and be-- tween. motionand standstill, which permits counting'by providing an impulse perrevolutionof' a-v shaft, which: provides an interlock betweenvariousmovingpartsof'an installation; which can be used as a jogging switch andinterlock for devices such as: conveyors, and which selectively operatesa plurality of independent switches according to the motion or restcon-= dition of the mechanism under study' or control. Other-object'sare to introduce an adjustable or fixed time delaybetweenthe-application of drivingmotion toadevice and actuation. of dependent.

devices such as switches accordingly, to: provide a: zero: motionindicator, and to provide. a. device o the general: type indicated.above: winch simple and inexpensive and; yet rugged, reliable, accurateandparticularly also very versatile for application: to; a large varietyof functions;

Devices according to the invention comprise a. housing containing;viscous liquid, at driving element such as a disk; and a driven membersuch. as another disk, mounted in. the, housin with driving: and,driven. portions adjacent. to each other. and with the liquid providinghydraulic, coupling. betweenthetwo portions, means for.transmittingmovementv to the driving element, an. actuatednmmber, a, magnet or ironelement carried. by one of the two members, and a. magnet. or, ironvelement, carried by. the

other member, magnet. and. iron-vv elements. being.

placed,.magnetically to. respond, to. a, change. of. position,therebetwe en, whereby movement. of: the. driving element causes changeof position of the driven member a-iiecting the actuated member.Preferably the actuated member switch, but any mechanical operator canbe used instead, such as a lever for moving a signalingelement oropening or closing: a latch or look mechanism. Biasing means such as aweight eccentri'cally mounted onthe driven member, or spring means areused for yi'el'dingly urging the driven member to holdits magneticelement in a normal position, so that rotation of the driving elementcauses the driven member to move the magnet to a position displacedclockwise or counterclockwise from the normal position to affect theother magnetic element and to actuate the device, If one or a pluralityof actuated members are disposed with their magnetic" elements such asiron armatures adjacent the path of the driven magnetic element, atnormal position or at one or more displaced positions on eachoreitherside of'a normalposition or'at both normal and displacedpositions, these members can be actuated" ina variety of ways,independently ordiscriminatory of the direction of rotation.

To provide fora minimum starting speed and to-i-ntroduce a time delaybetween the beginning of rotation of the driving element suchas a diskand the actuationof one of the devices through. the driven member suchas another disk, the liquid coupling between the disks can be varie sothat rotation of the driving disk does not move the driven disksufiiciently to a-fiect the magnetic element of the actuated device, orto introduce a predetermined slip between driving element anddrivenmember. The'magnitude of liquid coupling can bevaried by changingthe bias suchasweight of the magnet or other part mounted on the drivenmember, by changing the viscosity of the liquid in the housing or, withparticular convenience, by adjusting the spacing between the disks;

In a further-aspectthe driven member carries one or" more abutments, andthe housing or a structural component referred thereto carries a stopdisposed in the path of an abutment so that when the driving elementmoves the driven member the abutment engages the stop to hold the drivenmember in a predetermined position, the magnetic element of one or, moreoi" the actuated devices being located in corresponding position. Aplurality of abutments can be disposed in spaced positions on the drivenelement to move along spaced paths, the. stop being. ad'- justabl'e intoa selected path thereby presel'ecti'ng is athe position of magneticelements of the driven member and the actuated device.

In a more specific aspect the disks constituting driving element anddriven member are only partially immersed in the viscous liquid, and aredisposed with opposed faces parallel and closely adjacent to provide acapillary space for the viscous liquid therebetween, the disks beingeffectively coupled by a controllable capillary force acting in thespace, so that when the driving disk is rotated liquid will bedistributed over said faces and the driven disk will be coupled tothedriving disk with the above mentioned speed discrimination and timedelay.

These and other objects and aspects of the invention will be apparentfrom the following description of several embodiments which refer to adrawing wherein Fig. l is a side elevation of an actuator according tothe invention;

Fig. 2 is an end elevation corresponding to Fig. 1;

Fig. 3 is a section on line 3-3 of Fig. 2, with parts in elevation;

Fig. 4 is a section on line 4 of Fig. 3;

Fig. 5 is an enlarged section similar to Fig. 3, through switch andhousing, with the magnet in elevation and the other parts omitted;

Fig. 6 is a section corresponding to Fig. 4 of a second embodiment; and

Fig. '7 is a section similar to Fig. 5 of a third embodiment of theinvention, certain parts being omitted in Figs. 6 and 7.

The embodiment of the invention which is illustrated in Figs. 1 to 5 hasa housing I enclosing a chamber partially or wholly filled with aviscous liquid 2 such as hydraulic fluid of selected viscosity andmounting a shaft 3 which carries a driving disk 4 fixed to the shaft anda driven disk 6 freely rotating on the shaft. The driven disk 6 carriesa small permanent magnet l at its periphery. Mounted outside the housingis a mercury switch 8 or mechanical device 8a. (Fig. 7) having a movableiron element 9 or 9a respectively. It will be noted that the magneticelements 1 and 9 define a comparatively concentrated region of optimumresponse therebetween.

The housing I has a journal box H in which are mounted two rollerbearings l2 and a conventional sealing ring l3 respectively forsupporting the shaft 3 and preventing loss of the hydraulic fluid 2. Thedriving disk 4 is spaced from the inner bearing 12 by washers l4 andfixed to the shaft 3 with a screw IS. The inner end of the shaft I? isof reduced diameter to form a shoulder [8, the reduced portion beingthreaded to receive a nut [9 for clamping the inner race of a rollerbearing 2! against the shoulder l8. The driven disk 6 is secured to theouter race of bearing 2| by a set screw 22, the driven disk 6 being freeto rotate independently of the shaft 3, except as will be describedhereinafter.

The driven disk 6 carries near its periphery a magnet I for examplesecured by a machine screw 24 to a rearwardly extending boss 23. Themagnet l is held close to the rear wall 26 of the housing, which rearwall is formed of nonmagnetic material such as molded plastic.

Attached at the rear of the housing I is a bracket 21 to which one ormore spring detents 28 for firmly holding a mercury switch 8 areattached by screws 29 passing through holes 3!. Other mounting holes emand Slb are provided to attach additional detents (not shown) forholding additional switches serving purposes to be set forth below.

As shown in Fig. 5 the mercury switch 8 can be of conventional designwith a glass envelope 30 and two leads 32 one of which extends into apool of mercury Hg while the other is electrically connected through aspiral spring 33 to the armature 9 with wire finger 34 which dips intothe pool of mercury thus completing an electrical circuit when themagnet l attracts the armature 9. Instead of the mercury switch 8, apivoted lever 8a of a mechanical actuator may be mounted adjacent therear wall 26 of the housing I as shown in Fig. 7. The lever 8a carriesan armature 9a, and it will be understood that in this and analogousembodiments with little limitation on size or weight of the armature,components 1 and 9a, constituting magnetic elements, can beinterchanged. It will be further apparent that the separating wall 26can be part of a larger compartment, the magnetic link i, 9 providingfor mechanical separation of driven member 6 and actuator 8 or 8:1.Instead of a magnet and an iron armature, two magnets can be used asmagnetic elements.

In the position shown in Fig. 5 with magnet I opposite armature 9, thelatter is attracted, making contact at Hg and 35 as indicated in dot anddash outlines.

As shown in Figs. 3 and 4 the driven disk 6 carries a pair of vanes orabutments 3? near its periphery. A screw 38 fastened in the top of thehousing I extends with its end into the path of the vanes 3? for thepurpose of stopping rotary motion of the driven disk in either directionwhen the magnet l and the vanes 3? are in one of the positions la shownin Fig. i in dot and dash lines. In either of these positions the magneti will operate a mercury switch held in one of the clips or detentsmounted by means of holes Zia (Fig. 2) as described above. The armaturesof these switches can be disposed in appropriate positions to either sidof the central position shown in Figs. 2 and 3. It will be furtherunderstood that the lateral distances of these armatures can be renderedadjustable by appropriate conventional means.

As shown in Fig. 6 two or more vanes or abutments 31a or 311) may beprovided at either side of a line passing through the shaft axis and themagnet l in neutral position. The abutments 31a nearest that line arelocated nearer to the axis of the disk than vanes 37?). In thisembodiment a modified stop screw 38a is adjustable radially of thedriven disk so that it can be moved into the paths of the outer vanes31b as shown by its position in solid lines in Fig. 6 or into the pathof the inner vanes 3711i as shown by its position shown in broken lines3821 so that it can be selectively stopped by either a vane 3w or 3%respectively.

When the stop screw 36a is in the position shown in broken lines thedriven disk will be stopped in one of the broken line positions in ofthe magnet. When the stop screw 38a is in the position shown in solidlines the driven disk will be stopped with its magnet in one of thebroken line positions Tb. As already indicated, switch means 8 ormechanical actuator devices 3a may be mounted at positions correspondingto detent mounting holes 3la or 3th which again correspond respectivelyto vanes 37a or 3172. The switch 8 can also be moved from a detent seu et0 the holes 3m to a detent secured in the 5.: holes 3131. as the:vstop: screw: 3.311 is: adjusted. to thepath of vanes 331117..

As shownin Figs. hand-3 thehousing l; is provided"v with an; opening i]providing to the setscrew' 221 which ia-sten-sthe-dish: 6 to thebearing. 21.. A; screw 4:22 provides a closure for theopening d].

The-.operation of the actuator is as follows.

Assuming. that the: actuator is mounted in the position shown, theweight of the magnet inormallyholds the driven disk. tin the restposition shown in the. drawing insolid. lines. In this position themagnet-.11; is in operative relation to armature a (Fig. 5) or 9:1.(Fig. 7) such that the armature causes-the switch 8 to close or theactuating lever 3a to. move to a desired position. Whenthe driving shaft3,.which is connected to arotating mechanism, for example the shaft of amotor beginsatorotatathe hydraulic liquid effectively couplesthe drivingdisk to the driven disk:causing the drivendisk to rotate in the samedirection. The disk. and magnet return to normalu position, reactuatingswitch 8, only upon stoppage, or if desired minimum speed, of thedriving member.

If thehousing Iis full, or nearly full, of hydraulic liquid 2 the drivendisk will respond relatively' quickly. Ifthe housing is only partiallyfull as shownin. Eigs. 2' and 4, the hydraulic liquidwill be drawnbetween the disks at a certain rate until sufficient interracialfriction or capillary attraction is provided to overcome thetendency-of-Ithemagnet or other weight to hold the driven disk in normalor rest position. In addition to amount of liquidand speed rotation, the

response time also depends on the viscosity of the liquid and'thespacing between driving and drivendisks. The disk will then move themagnet to the position defined by stop 33 or to one of: thepositions idor lb. More time is needed to lift the magnet to a more remotelydisplaced position such as it than to a less remotely displacedpcsition-such as To.

As the magnet moves from its normal position it will move out ofoperative relation with the switch 8'. allowing the armature locatedadjacent the normal position lot the magnet to move its contact finger34 from-the mercury pool, with a certain time delay between beginning ofmotion and actuation of the switch. When the F magnet '7 moves into oneof the displaced positions id or iii it will remain there operating thearmature of a switch if such is located in that positicn. Whether thedriven disk moves in either clockwise or counterclockwise direction theswitch at neutral position will be allowed to open. If switches aremounted at the displaced positions one of them will be actuated. Thusthe switch. at normal position may be employed to discriminate betweenrotation and non-rotation of the mechanism attached to the driving shaft3, while switches located adjacent displaced positions la or lbcan beused to indicate the direction-of rotation-of the shaft.

Displaced switches alone, without normally affected switch 8 willperform the function of switch 8,? as well'as the directional function,with an additional time delay, if desired adjustable by means of a stopsimilar or analogous to screw 38a.

The return time upon stoppage of shaft 3 or rotation, fallingbelowagiven rate can be ad- .li stedto. determine time intervalsbetween-rerspective conditioning. of; two switches in post.-

tions, such; as 3.1; and. 31mm; between actuati nandircactuationphasingleswitch at-.3 l

If the, :stop: 38: isgentirely: withdrawn, the actu: ator; can.bemsed;as a: counter effecting one or more impulses per shaft rotation, the.pha-serelation; of: movement: and impulse and the number of. impulses?depending; upon the arrangement of switchesand selection of couplingcharacteristics..-

In additiomswitches .locateda-t displacedpositions will; giveaqualitative indication of the speedi of the: shaft; sinceia switchlocated adjacentiailessremotely displacedpositionsuch as 10: willrespond at a givenspeed: prior; to the response of a switch located at amore remotely displaced position such: as lb; analogously, two switchesat different positions will respond: to differentaspeedsr: with the sametime delay. Generally speaking; the three variables, switchposition;speed. of; driving member and response delay, canibedefinitely;interrelated.

The: timedelayrbetweenthe beginning of rotation of the drivendiskzda andthe operationof a switch may be controlledor adjusted by varying. eitherthe hydrauliocoupling between the disks or theadjustment-off the stopscrew 38a. or the vane positions; or. by; changing the bias of thedriven disk 6 This can be done by changing the weighting means of:driven disk 6; or by adjusting: biasing; means. which. are independentof' gravity.- Fig. 6 shows assuch meanssprings 5|, 52. interposedbetweenv housing I and. disk 8. Such springs can-be rendered adjustableby conventional meansand set tozbias-the driven member. inthe-desirednormal.position. The hydraulic. coupling betweenthe disks maybe increased set screw: 22'; By. insertingascrew driver through thisopening thesetscrew. 22'may. be loosened and the driven disk. shiftedaxiallyon the bear- J ing 2! to adjust the spacing between the disks.

The weighting of the driven disk may be increased. by replacing themagnet T with one of greater. Weight, or by adding a non-magneticweight. may. be adjusted'in' or out of the paths of one of the stopvanes37a or 3'") thereby determining the angle through which the driven diskmay rotateand'also selecting aswitch at one of the displacedpositionsFa-or lb for continuous operationby themagnet 7.

By pro-perchoice of the various effective characteristics such as fluidviscosity, degree of filling, disk distanceand'biasing force,- a minimumeffective speed as well aspredeterminedtime-delay'of actuation uponreaching such speed can be selected to efiect response of' a switch orswitches-or-other actuators at either normal or displaced position. Thusa switch 8 in the positionof'Fig; 2 can be made to respond only if theshafts" rotates at agiven speed, with predeterminedtimedelay afterthatspeed is reached.

Bydifferently distancing the corresponding driven stops (such- 31) oneither side of a fixed stop (such as 38*), d-ifferentresponse speeds andtime delays can be provided for'respective scnsesc'fmovement;Adjustability of these-distances and of" the corresponding responsecharacte-ristics be provided by conventional means: applied to :mov-ableor-fixed stops or both.

It willi l'lQW be. evident: that: devices. built in.

As previously described the stop 38a accordance with the invention areadaptable to varous purposes involving functions such as time delay,jugging, directional discrimination, distinction between operation andnon-operation, speed detection, interlocking of several components,speed limiting, supervision of reversing, overrunning control,protection against back spin, counting, and combinations of suchfunctions.

It should be understood that the present disclosure is for the purposeof illustration only and that this invention includes all modificationsand equivalents which fall within the scope of the appended claims.

We claim:

1. An actuator comprising a housing containing viscous liquid, a drivingelement and a driven member mounted in said housing with driving anddriven respectively adjacent to each other with said liquid providinghydraulic coupling therebetween, means for transmitting movement to thedriving element, an actuated member mounted outside said housing, aconcentrated magnetic element carried by one of said members, a secondconcentrated magnetic element carried by the other member, and stopmeans for limiting conjoint movement of said driving element and saiddriven member, said magnetic elements being placed relatively to saidstop means to move said actuated member upon change of positiontherebetween, whereby moveent of the driving element causes delayedresponse of said actuated member.

2. Actuator according to claim 1 further comprising biasing meansyieldingly urging the driven member to hold its magnetic element innormal position, whereby rotation of the driving element causes thedriven member to change said position, affecting said actuated member.

3. Actuator according to claim 1 wherein said stop means includescorresponding stop members mounted on said driven member and saidhousing respectively, to stop movement of the driven member afterinitial movement, while said driving element continues to move.

. 4. An actuator comprising a housing containing viscous liquid, adriving rotatable disk and a driven rotatable disk both mounted in saidhousing with said liquid providing hydraulic coupling between the disks,means for transmitting rotary movement to the driving disk, aconcentrated magnetic element carried by the driven disk, stop means forlimiting conjoint movement of said disks, and an actuated device havinga concentrated magnetic element fixed relatively to said housing torespond to a change of position between the magnetic elements.

5. Actuator according to claim 4 further comprising means for biasingsaid driven disk to urge its magnetic element to a normal position,whereby rotation of the driving disk causes the driven disk to move itsmagnetic element from said normal position to affect said actuateddevice.

6. Actuator according to claim 5 wherein said biasing means normallyurges the magnetic element of said driven disk to a normal position andwherein said second magnetic element is located adjacent said normalposition, whereby rotary movement in either of two directions actuatessaid device.

'7. Actuator according to claim 5 wherein said biasing means normallyurges the magnetic element of said driven disk to a normal position andwherein said second magnetic element is disposed at a location adjacentthe path of the first magnetic element but spaced from said normalposition, whereby said device is actuated by rotary movement in onedirection.

8. Actuator according to claim 5 comprising an additional actuateddevice said driven disk being normally biased to urge its magneticelement to a normal position and said two actuated devices being locatedwith their magnetic elements adjacent the path of the magnetic elementof the driven disk at each side of said normal position respectively,whereby one of said devices i operated according to the direction ofsaid rotary movement.

9. Actuator according to claim 5 having two additional actuated devicesand being characterized in that said driven disk is normally biased tourge its magnetic element to a normal position and in that said threeactuated devices are located with their magnetic elements adjacent thepath of the magnetic element of the driven disk, one element adjacentsaid normal position, and one of the remaining elements at each side ofsaid normal position respectively, whereby one of said devices isselectively actuated in the absence of said rotary movement or by rotarymovement in either direction respectively.

10. Actuator according to claim 5 wherein said biasing means comprisesspring means interposed between said driven disk and said housing tourge its magnetic element to a normal position, whereby rotation of thedriving disk causes the driven disk to move its magnetic element fromsaid normal position and to affect said device.

11. Actuator according to claim 4 wherein said driven disk carries amagnet and said actuated device carries an iron armature element.

12. An actuator comprising a housing containing viscous liquid, adriving rotatable disk and a driven rotatable disk both mounted in saidhousing with a space therebetween and with said liquid providinghydraulic coupling through said space, means for transmitting rotarymovement to the driving disk, a magnetic element carried by the drivendisk, an actuated device having a magnetic element fixed relatively tosaid housing to respond to a change of position between the magneticelements, and means for adjusting said coupling thereby to vary apredetermined period between initiation of driving and effective changeof position between the magnetic elements.

13. Actuator according to claim 12 characterized in that said adjustingmeans comprises means for varying the space between said disks.

14. Actuator according to claim 13 further characterized by shaft meansadjustably carrying said driving disk, bearing means for rotativelysupporting said driven disk on said shaft means and means for adjustingthe distance between said disks.

15. Actuator according to claim 14 wherein said driving disk is fastenedto said shaft and said driven disk is axially adjustable on saidbearing.

16. The actuator according to claim 14 wherein said driven disk isfastened to said bearing with a set screw and said housing has anopening afforcling access to said screw.

17. An actuator comprising a housing containing viscous liquid, adriving rotatable disk and a driven rotatable disk both mounted in saidhousing with said liquid providing a hydraulic coupling between thedisks, means for transmitting rotary movement to the driving disk, a

magnetic element carried by the driven disk, an abutment mounted on thedriven disk, a stop mounted on the housing and disposed in the path ofsaid abutment to hold the driven disk in a displaced position after apredetermined period of rotation of the driving disk causing the drivendisk to move its magnetic element from a normal position to saiddisplaced position, and an actuated device having a magnetic elementfixed in predetermined position relatively to said stop, whereby the twomagnetic elements can be held in predetermined relative position duringrotation of the driving disk.

18. Actuator according to claim 17, wherein said driven disk carries anabutment on either side of said stop.

19. Actuator according to claim 17 characterized in that said drivendisk carries a plurality of abutments radially spaced to stop the drivendisk in at least two displaced positions at one side of said stop, saidstop being adjustable selectively to extend into the path of one of saidabutments.

20. An actuator comprising a housing containing viscous liquid, adriving rotatable disk and a driven rotatable disk mounted in saidhousing, said disks being only partially immersed in said liquid, meansfor transmitting rotary movement to one of the disks, a concentratedmagnetic element carried by the other disk, and an actuated devicehaving a second concentrated magnetic element fixed relatively to anormal position of the first magnetic element to respond to a change ofposition between the two elements, the opposed faces of said disks beingdistanced to form a capillary space for liquid therebetween so that saiddisks are coupled by a predeterminable capillary force, whereby thedriving disk when started by said transmitting means distributes liquidover said faces and the driven disk is moved to afiect said device aftera time interval dependent upon the building up of said capillary force.

21. Actuator according to claim 20 characterized by means for adjustingthe spacing between said disks to vary said capillary force, wherebysaid interval may be varied.

22. An actuator comprising a housing containing viscous liquid, adriving rotatable disk and a driven rotatable disk both mounted in saidhousing with said liquid providing hydraulic coupling between the disks,means for transmitting rotary movement to the driving disk, aconcentrated magnetic element carried by the driven disk, stop means forlimiting conjoint movement of said disks, an actuated device having aconcentrated magnetic element fixed relatively to said housing torespond to a change of position between the magnetic elements, andbiasing means including an eccentric weight on said driven disk forbiasing the driven disk to urge its magnetic element to a normalposition, whereby rotation of the driving disk causes the driven disk tomove its magnetic element from said normal position and to afiect saiddevice.

GEORGE A. WINTERBURN.

CLARENCE B. WALWORTH. LEROY E. LAWRENCE.

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